Recently, the touch panel has become indispensable as means of input for electronic devices. From comparatively large devices such as televisions, monitors, and whiteboards to comparatively small devices such as smartphones and tablets, the touch panel has come to be used generally as a means of input.
Additionally, there have been many proposals for touch panel systems equipped with a dedicated touch pen able to provide not only information related to the touch position, but also additional information (for example, information such as the state of whether or not a button is being pressed, and pen pressure), enabling input with not only a finger but also the dedicated touch pen, and thus enabling the realization of more precise and varied input.
For example, PTL 1 discloses a touch panel system enabling respective touch positions to be detected accurately, even when touch operations by multiple digital pens or fingers are performed simultaneously.